AMD ATHLON 8 - Manual (Page 36)

24 Advanced 266 Front-Side Bus AMD Athlon™ XP Processor Model 8 Specifications Chapter 6
AMD Athlon™ XP Processor Model 8 Data Sheet 25175H—March 2003
Preliminary Information
6.2 Advanced 266 FSB AMD Athlon™ XP Processor Model 8
SYSCLK and SYSCLK# AC Characteristics
Table 3 shows the SYSCLK/SYSCLK# differential clock AC
characteristics of this processor.
.
Figure 8 shows a sample waveform of the SYSCLK signal.
Figure 8. SYSCLK Waveform
Table 3. SYSCLK and SYSCLK# AC Characteristics
Symbol Parameter Description Minimum Maximum Units Notes
Clock Frequency 50 133 MHz 1
Duty Cycle 30% 70%
t
1
Period 7.5 ns 2, 3
t
2
High Time 1.05 ns
t
3
Low Time 1.05 ns
t
4
Fall Time 2 ns
t
5
Rise Time 2 ns
Period Stability
± 300
ps
Notes:
1. The AMD Athlon™ system bus operates at twice this clock frequency.
2. Circuitry driving the AMD Athlon system bus clock inputs must exhibit a suitably low closed-loop jitter bandwidth to allow the PLL
to track the jitter. The –20dB attenuation point, as measured into a 20 - or 30 - pF load must be less than 500 kHz.
3. Circuitry driving the AMD Athlon system bus clock inputs may purposely alter the AMD Athlon system bus clock frequency (spread
spectrum clock generators). In no cases can the AMD Athlon system bus period violate the minimum specification above.
AMD Athlon system bus clock inputs can vary from 100% of the specified frequency to 99% of the specified frequency at a
maximum rate of 100 kHz.
t
5
V
CROSS
t
2
t
3
t
4
t
1
V
Threshold-AC